Adhesive compositions



- Patented Oct. 9, 1945 Cross Reference 38ml) m ADHESIVE COMPOSITIONSJoseph Lloyd, Pendleton, Salford 6, England, assignor to J. Mandleberg &Company Limited, Pendleton, England, a British company No Drawing.Application May 25, 1942, Serial No. 444,425. In Great Britain October29, 1941 4 Claims.

This invention has for its object to provide an adhesive compositionuseful for many services, some of which are herein indicated, in whichthe adhesive property is retained over long periods, the material beingcapable of being readily stripped from a. surface to which it has beenapplied either directly by brushing, pasting or otherwise or upon asuitable fabric, paper or like carnet.

The improved adhesive composition comprises natural rubber or syntheticrubber, together with resinous gutta percha or balata or resinous rubber(which bodies have adhesive properties), stabilising agents such asmagnesium usta, and rubber anti-oxidants such as Flectol H (Monsantoproduct, acetone-aniline condensation product) or other well knownpreservative, together with where necessary colouring matter, lakecolours or pigments. Carbon black, lithopone or titanium oxide may beadded to give opacity and proof against light infiltration orpenetration. Zinc oxide, and aluminium or other metallic powder may beadded for specific services.

The ingredients are mixed together on mills or internal mixers as usedin the rubber industry and the dry composition is converted into a paintor spreading mixture by the addition of a suitable solvent such aspetroleum or coal tar solvents or a non-inflammable solvent such ascarbon tetrachloride.

The correct consistency of the mass may be obtained for any purpose bymodification of the milling procedure and the proportion of solvent.

The mass or composition may be made more homogeneous and free flowing bythe addition of waxes or oils such as paraflin wax.

A transparent adhesive covering is sometimes required as an adhesivebacking to translucent paper as for example for tracing and masking inphotography for colour reproduction and tinting. Such an adhesivecovering is prepared by using pale crepe rubber, resinous gutta percha,balata or rubber, which will not stain or colour the mixture, magnesiumusta and a colourless anti-oxidant, together with the appropriate amountof solvent.

A self vulcanising adhesive mixture may be produced by using twomixtures, one containing one or more vulcanisation accelerators, and theother containing sulphur or other substance to promote vulcanisation.The two mixtures are brought together just prior to use as an adhesiveafter which the rubber will vulcanise in a few hours at atmospherictemperature; the adhesive property persists however for a considerableeriod.

My improved adhesive may be used by itself and rubbed oil dry or removedby a suitable solvent. Or it may be applied to a suitable backing orcarrier for use as a readily removable mask in photography, motorvehicle spray painting and in printing. It may be used to secure postersor the like on hoardings, windows, showcases &c., the posters beingreadily stripped from theirsupports when required to be removed. It yalso be used in bookbinding, in the manufacture of leather and fancygoods, ,ihrseemfiig wall paper, blackout materials 8w. Further it can beapplied to materials which have been previously coated with rubberprooflngs or other products, such as synthetic rubber or syntheticresins and cellulose. This prepared material can be used as permanentlyadhesive taping strips or sheets for various purposes.

Example I A typical composition by weight of a light resisting adhesiveis:

If the solvent be carbon tetrachloride, from 48 to 80 lbs. by weight areused; if petroleum or coal tar solvent, from 24 to 40 lbs. are used.

Example II A typical transparent adhesive is compounded as follows:

Pale crepe rubber pounds 10 Gutta resin do 2 Magnesium usta do...... 1Flectol H (Monsanto product, acetone-aniline condensation product) .oz 1

The solvent is as in the previous example.

Example III If to one portion of a composition as in Example I there beadded 2 oz. of Vulcafor Z. D. C.

o (I. C. I. product, zinc diethyl dithiocarbamate) variety, then ifthese two portions are mixed together just prior to use, the rubbercontent will resin and balata resin, in the proportion of about bevulcanised in a few hours at atmospheric tem- 5 to 1 by weight.peratures and the resulting adhesive will retain 2. A transparentadhesive composition cornits adhesive property for a considerableperiod. prising 10 parts (by weight) pale crepe rubber, Example IV 6 2parts gutta resin, 1 part magnesium oxide, about 1 5 part of a rubberanti-oxidant, and 24-80 parts Similarly if to one portion of acomposition as of an organic solvent, and adapted to remain 111 Example1 there a ed 2% Vuleafer tacky after evaporation of the solvent. Z. D.C. (I. C. I. product, zinc diethyl dithioear- 3, An opaque ivcomposiflgn, comprising amabe) and /2 oz. of Vulcafor Z. I. X. C- 10 10parts (by weight) smoked sheet rubber, 2 parts p u z n s propy Xanthate)an if to gutta resin, 1 part magnesium oxide, 4 parts zinc other similarportion of the same composition xide, 2 parts carbon black, about 1 partof a there e add d 9 /2 o of su h pr a y the rubber anti-oxidant, and24-80 parts of an orprecipitated variety, then it these two portionsganic solvent, and adapted to remain tacky after are mixed together justprim to use; the rubber 15 evaporation of th solvent.

4. A method of obtaining an adhesive composimospheric temperaturesandthe resulting transtion adapted. to remain tacky aftervulcanisation,v parent adhesive will retain its adhesive property for acon i erable pe i portion of a composition as claimed in claim 1 What Iclaim is:

20 and containing sulphur, and another portion of 1. A non-hardening,permanently tacky, adhesive composition, containing rubber and asubstance selected from the group of gutta

